1)u should use -r's, if you cant wait, use a +r for now, but change it, you dont want to ruin the laser, do you?
2)You can use your HDD but it will be a little tiring process, well worth it tho, if you ask me. back up your music, format the disc with fat32, then split it in two pieces, the first one should be primary and active. Size is up to you, but bear in mind, in the first part we ll put the wii games, so make it adequately big. 100G at least, as games are 2-4 Gigs, best ones are 4. So, then u format the first part with WBFS manager,put the games in it, in second part, u put the music, and u can alos use it for your homebrew apps, wads, usbloaderGX covers, emulators.... so kinda rocks.
You can also play your music with it, you must install ios202 for this reason see
this MPlayer CE - WiiBrew
you can put the app in teh second partition, and the files also and play them from there, also movies and stuff, DVD palyback not supported for now i guess.
3) you can update the HBC no problem